In an image forming apparatus, it is required to prevent dew condensation and operation failures due to environmental variations, e.g., a rapid room-temperature change. In the following, the image forming apparatus is mainly described as an example. The above-mentioned rapid temperature change is caused depending on a season and a region in which the image forming apparatus is installed, and is further caused depending on environmental variations, e.g., a rapid room-temperature change due to coldness at night or in the morning, or air conditioning after the beginning of work in a company. Such a rapid temperature change may inhibit satisfactory image formation.
In order to prevent dew condensation, there is known a method of preventing the dew condensation by adding, after the image forming apparatus is installed, an environment heater to the image forming apparatus in accordance with the usage environment.
In recent years, the image forming apparatus is required to have more stable image quality and longer life. In order to satisfy those requirements, it is necessary to further stabilize, in an electrophotographic process, the temperature of the image forming apparatus, and, in particular, the temperature of a part around a photosensitive drum. Further, also in a general information processing apparatus, for longer life, and the like, it is required to stabilize the temperature at a specific unit of the information processing apparatus.
As the environment heater, there is known an alternating current (AC) heater configured to use, as a power supply, an AC commercial power supply to which the image forming apparatus is connected.
In Japanese Patent Application Laid-Open No. 2009-216827, there is described an environment heater to be selectively mounted to an apparatus main body depending on the voltage of the commercial power supply to be used.